Global Navigation Satellite System (GNSS) receivers have been incorporated into a multitude of devices, including mobile devices such as mobile phones, tablet computers, satellite navigation systems, and other portable devices. GNSS receivers have also been incorporated into wireless access points and terrestrial transceivers, such as femtocells to provide the wireless access point or terrestrial transceiver with precise location information.
Mobile devices, such as mobile phones, tablets, and other such devices that may make use of GNSS signals for positioning often face power constraints due to the limited size of the on-board batteries of such devices. GNSS positioning methods can have a significant impact on battery life of a mobile device. For example, in a conventional GNSS receiver, navigation is performed to achieve a required accuracy and the power consumption associated with the GNSS receiver is optimized to provide the required accuracy. However, this approach is suboptimal in situations where the power consumption associated with obtaining the position of the mobile device is more important than the accuracy of the position determination. A conventional approach to this problem is to reduce the accuracy requirements of the GNSS receiver to reduce the power consumption by the GNSS receiver. However, this approach may not be uniformly effective given the variable nature of GNSS signal conditions. The GNSS receiver may exceed the desired power consumption where the GNSS signal conditions are poor even if the accuracy requirements have been reduced. For example, in a densely built up urban environment the GNSS signals may be obstructed, at least in part, by buildings and other structures in the environment that can cause the accuracy to degrade. As a result, the GNSS receiver may consume more power attempting to acquire signals from a sufficient number of GNSS satellite vehicles (SVs) to be able to determine a position for the mobile device.